Not only was Dunlap's Creek Bridge the first cast-iron bridge in America, it was the first metal bridge anywhere to use what its builder, Capt. Richard Delafield, U.S. Army Corps of Engineers, described as "standardized, interchangeable, manufactured parts." The bridge was built as part of the federal government's effort to make repairs on the National Road before handing authority over to the states. Dunlap's Creek at Brownsville was an especially troublesome crossing, having destroyed three previous bridges since 1801.
The significance of the 15-mile Whitewater Canal was not in its ability to create a profit, but rather its effect on the economic growth of the Whitewater River Valley, considered the gateway to the interior of Indiana. Before the canal, travel was challenging. Most waterways in Indiana were only navigable by canoe, and the alternative - horse and wagon - was difficult, slow and expensive.